In conventional methods to determine microorganisms, such as bacteria and fungii, the determination is carried out in such a manner that microorganisms are picked up from a specimen; the number of the microorganisms is appropriately adjusted and then cultivated for about 24 to 48 hours using an agar medium; the judgement of the microorganism is done with human eyes. In another method, it is known to vegetate microorganisms picked up from specimen on a culture, where chromo-enzyme has been mixed, and the microorganisms are cultivated for about 24˜48 hours; the judgement of the microorganism is conducted using human eyes by dissolving the chromo-enzyme and developing the color with β-galactositase enzyme.
Further, the present inventor discloses a method for determining microorganism in Japanese Patent No. 2979383. The technique in this patent is that: a microorganism is double-stained with appropriate fluorescent reagents and the thus stained microorganism is processed so as to prevent that the fluorescent reagents flow out from the cells of the microorganism; then the thus processed microorganism is dropped onto a light permeable plate and an excited light is illuminated on the plate from underneath; the determination is carried out by human eye using a magnifying lens. According to this method, the microorganism is double-stained for obtaining different fluorescence from vital cells and dead cells, it is therefore possible to determine if the subjected microorganism is vital or dead. Furthermore, it is possible to judge the type and the number of the microorganism by measuring the dimension and counting the quantity of the fluorescents.
However, in a case where it is required to determine a microorganism immediately, the conventional method using a culture is not practical because it is required to cultivate microorganism for a long time. The other demerits are that: the types of microorganisms which are available to be determined are limited to only a few, such as Escherichia coli or general vital microorganisms, and it is difficult to judge if the microorganism is vital or dead. On the other hand, the method disclosed in the patent owned by the present applicant is to determine the stained microorganism with the aid of fluorescent reagents by human eyes using a magnifying lens. Accordingly, it has been desired to determine microorganisms more precisely.
The present invention has been carried out to solve the above-mentioned tasks and has for its purpose to provide a method and an apparatus for immediately determining microorganisms, where the amount or the type of bacterium or fungus can be judged and the judgement if the microorganism is vital or dead can be done with an extremely high accuracy and in a very short time period.